Floating supporter for drill pipe



June 17, 1930.

J. A. zUBmN FLOATING SUPPORTER FOR DRILL PIPE Filed Apiil" 22, 1929 [/vl/E v Toe; (/05)? Zub'n,

Patented June-17, 1930- UNITED: STATES PATENT OFF-ICE JOHN LZUBLI'N, LOSAKGELES, CALIFORNIA FLOATING SUPPORTER FOB DBILI. PIPE application med Aril 22,

which drill pipe is rotated bya rotary machine in the derrick of thewell. The drill pipe consists of stands of pipe approximately eightyfeet in length, which are connected together by-tool joints. It iscommon practice at the present time to support the drill pipe by meansof a swivel head at the surface of the ground. It is not unusual at thepresent time to drill wells 'to a depth of five or six thousand feet. Inview of the enormous weight of the drill pipe, there is a; markedtendency for the tool joints to be pulled apart and the drill pipe toseparate.

' It is an object of my invention to provide the drill pipe with one ora plurality of floats or buoys attached. thereto which support a portionor all of the-weight of the drill pipe, zsthus reducing the liability ofthe drill pipe being separated at the tool joints. My invention consistsof a buoy which sur-. rounds the drill pipe and which may be rigidlyattached to the drill pipe or maybe held in position by engagement witha shoulder of one of the tool joints on the drill pipe. It is the usualpractice in drilling a well by the rotary system to pump rotary muddownward through the drill pipe, this mud issuing from the bit andpassing upward through the well around the drill pipe.- This rotary mudat a depth of about six thousand feet is at a pressure around threethousand pounds per square inch. It is therefore necessary to constructthe buoys so that they will not be collapsedby this high pressure.

It'is an object of my invention to provide a buoy having a closedchamber which may be filled with a gas under pressure. Byapproximatingthe depth at which the buoy is to operate, the pressure at which the gasshould be compressed can be determined. Gas is then compressed to thiscertain pressure in the chamber of the buoy and lowere into place. Thepressure of the rotary mud 1929. Serial No. $57,009;

is therefore opposed by the gas pressure withm the bu'oy, and thetendency for the buoy to collapse 1s reduced so that collapsing is notliable to occur. These results may also be accomplished by fillingthefloat with a non-compressible fluid having a lesser specific gravitythan the rotary mud.

It is the present practice to provide adrill p1pe with wear preventersin order to prevent the drill pipe from engaging the walls of the holeand wearing away the pipe or tool joints or the well casing which hasbeen installed in the well.

It is anobject of myinvention to provide a buoy for the purposehereinbefore mentioned, which is useful also in the capacity of a wearpreventer.

A still further object of my invention is to provide a buoy forsupporting at least a part of the weight ofthe drill pipe, this buoybeing rotatable on the drill pipe.

Referring to the drawing in which my inventionis illustrated: a a Fig. 1is a utility view.

Fig. 2 is an enlarged view showing the buoy of my invention m section.

Fig. 3 is a section taken on the line 3 of Fig. 2. j Fig. 4 is a viewillustrating another form of my invention. 1

Referring to the drawlng n deta l, the numeral '11 represents a wellwhich is being drilled by a bit 12 secured to the lower end of a drillpipe sists of stands of pipe 15 connected together by tool joints 16.The drill pipe is rotated by a rotary machine 18. The upper end of thedrill pipe, 14 is connected to a swlvel head 19 by which a portion ofthe weight of thedrill pipe may be supported. Rotary mud, is supplied tothe drill pipe by a pump 20 connected to the swivel by a conduit 21.

In this view (Fig. 1) the numeral 25 .desig nates a buoy incorporatingthe features of my invention The details of the buoy are shown: in Fi 2and 3. Referring to these figures, the iuoy 25 consists of a shell 26havmg shell 26 provides an annular fluid chamber 14. This drill pipe 14cona central cylindrical opening 27 d through which the drill pipe 14extends. The

28. Fluid or gas under pressure may be introduced into the chamber 28through a valveclqsed pipe 29. The outer cylindrical wall provided inshallow Wells.

In the operation of the invention, the buoys being filled with the ,gasare of a less .specific gravity than the rotary mud which fills thewell. For this-reason the bhioys tend to support the drill pipe.Sufiicient buoys are providedso that the weight which must be supportedby the swivel head.19 is not great enough to create thedanger of thedrill pipe separating at any of the tool joints 16. The

' rubber wall 32 reduces the friction between therefore,

, atmosph the buoy and the wall of the well, and any wear which occurswill be on this rubber wall 32. The outerdiameter of the buoy is greater than the outer diameter of the tool joints; the buoys act as wearpreventers, preventing the, tool joints or any portion of the tooljoints from engaging the side of the well.

It is possible to determine at approximately what level the buoys willoperate, and this being known, it is possible to determine the,

pressure of the rotary mud at that level. Let us assume that a buoy isintended to operate v From'the foregoingdescription it will be seen thatb using myinventmn the liability of the dri pipe separating due toitsown weight will be eliminated. My invention is designed so that it isnot necessary to reconstruct the drill pipe, but on the other hand, itmay be applied to any drill pipe now in use. The buoy not only acts as aflotation means .for the drill pi e but also acts as a wear .preventerand W111. protect the drill pipe and well casing able extent.

I claim as my invention:

1. In apparatus for use in a well, the combination of: a column forextension into the well; and a buoy rotatable on said column forsupporting said column.

2. In apparatus'for use in a well, the combination of: a column forextension into the from be ng worn to any appreci- -well; anda pluralityof buoys rotatable on said column for supporting said column atdifferent places. a

3. In apparatus for use in a well, the combination of: a column forextension into the well; and a buoy rotatable on said column forsupportin said column, the interior of said buoy being filled with afluid under pressure. x

In testimony whereof, I have hereunto set my hand atLos Angeles,California, this 16th day of April, 1929.

JOHN A. ZUBLIN' at aflevel of six thousand feet. The rotary mu pressureat this point is three thousand pounds per square inch. If there wereonly eric pressure in the chamber '28,

the collapsing forces on the buoy would be very great and the buoy mightcollapse. By placing the gas in the chamber 28 under a pressure so as toreduce the difference in pressure of the interior and exterior, thepressure of the rotar mud is op osed andthere is no danger of/he buoycollapsing.

The collapsing orces on the buoy-are in proportion to the difi'erence inpressure'in the chamber and around the buoy-therefore the collapsingrotatably supported at each en 10, so that the buoy is rotatable on thedrill forces may be reduced to a safe margin b at of the 'pressure ofthe rotary mud. a

Fig. 4 I illustrate a buoy 25' of substantia ly the same construction asthat shown 1 in Figs. 1, 2, and 3. This buoy, however, is

by a bearing pipe.- In this form of the invention, when the buoy engagesthe wall of the well, the buoy remains stationary and the drill vplacing a ressure in the; chamber 28 which is below t ipe ro- .tates,the frict on being consumed in t e bearlugs 40. U J

